Yesterday, Rob told you about the first public tasting of a burger that was grown in a laboratory, from strips of flesh built up from muscle stem cells. I found a couple of great links today that build on that news. First: The secret ingredient in lab-grown meat is fetal cow blood. (It’s both a significant part of the high price of lab meat, and a reason why your vegan friend won’t be eating lab meat anytime soon.) Also be sure to check out synthetic biologist Christina Agapakis’ perspective — she tones down some of the hype while making it clear why lab meat is still pretty impressive.